US20230398906A1 - Method for controlling a power assembly - Google Patents
Method for controlling a power assembly Download PDFInfo
- Publication number
- US20230398906A1 US20230398906A1 US18/334,798 US202318334798A US2023398906A1 US 20230398906 A1 US20230398906 A1 US 20230398906A1 US 202318334798 A US202318334798 A US 202318334798A US 2023398906 A1 US2023398906 A1 US 2023398906A1
- Authority
- US
- United States
- Prior art keywords
- power
- fuel cell
- time period
- power demand
- threshold
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 39
- 239000000446 fuel Substances 0.000 claims abstract description 144
- 238000004146 energy storage Methods 0.000 claims abstract description 20
- 230000004044 response Effects 0.000 claims abstract description 8
- 230000015556 catabolic process Effects 0.000 claims description 13
- 238000006731 degradation reaction Methods 0.000 claims description 13
- 238000004590 computer program Methods 0.000 claims description 12
- 230000006870 function Effects 0.000 description 13
- 230000001419 dependent effect Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 241001246312 Otis Species 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000018109 developmental process Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 238000004378 air conditioning Methods 0.000 description 1
- 230000006399 behavior Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000011217 control strategy Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 230000000977 initiatory effect Effects 0.000 description 1
- 238000007726 management method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000021715 photosynthesis, light harvesting Effects 0.000 description 1
- 230000000153 supplemental effect Effects 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
- B60L58/40—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for controlling a combination of batteries and fuel cells
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L50/00—Electric propulsion with power supplied within the vehicle
- B60L50/50—Electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells
- B60L50/70—Electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells using power supplied by fuel cells
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L50/00—Electric propulsion with power supplied within the vehicle
- B60L50/50—Electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells
- B60L50/70—Electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells using power supplied by fuel cells
- B60L50/71—Arrangement of fuel cells within vehicles specially adapted for electric vehicles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L50/00—Electric propulsion with power supplied within the vehicle
- B60L50/50—Electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells
- B60L50/75—Electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells using propulsion power supplied by both fuel cells and batteries
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L53/00—Methods of charging batteries, specially adapted for electric vehicles; Charging stations or on-board charging equipment therefor; Exchange of energy storage elements in electric vehicles
- B60L53/50—Charging stations characterised by energy-storage or power-generation means
- B60L53/54—Fuel cells
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
- B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
- B60L58/12—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries responding to state of charge [SoC]
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
- B60L58/30—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling fuel cells
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W10/00—Conjoint control of vehicle sub-units of different type or different function
- B60W10/28—Conjoint control of vehicle sub-units of different type or different function including control of fuel cells
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M16/00—Structural combinations of different types of electrochemical generators
- H01M16/003—Structural combinations of different types of electrochemical generators of fuel cells with other electrochemical devices, e.g. capacitors, electrolysers
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M16/00—Structural combinations of different types of electrochemical generators
- H01M16/003—Structural combinations of different types of electrochemical generators of fuel cells with other electrochemical devices, e.g. capacitors, electrolysers
- H01M16/006—Structural combinations of different types of electrochemical generators of fuel cells with other electrochemical devices, e.g. capacitors, electrolysers of fuel cells with rechargeable batteries
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04223—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids during start-up or shut-down; Depolarisation or activation, e.g. purging; Means for short-circuiting defective fuel cells
- H01M8/04228—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids during start-up or shut-down; Depolarisation or activation, e.g. purging; Means for short-circuiting defective fuel cells during shut-down
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04298—Processes for controlling fuel cells or fuel cell systems
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04298—Processes for controlling fuel cells or fuel cell systems
- H01M8/043—Processes for controlling fuel cells or fuel cell systems applied during specific periods
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04298—Processes for controlling fuel cells or fuel cell systems
- H01M8/04313—Processes for controlling fuel cells or fuel cell systems characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
- H01M8/04537—Electric variables
- H01M8/04604—Power, energy, capacity or load
- H01M8/04626—Power, energy, capacity or load of auxiliary devices, e.g. batteries, capacitors
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04298—Processes for controlling fuel cells or fuel cell systems
- H01M8/04694—Processes for controlling fuel cells or fuel cell systems characterised by variables to be controlled
- H01M8/04858—Electric variables
- H01M8/04925—Power, energy, capacity or load
- H01M8/0494—Power, energy, capacity or load of fuel cell stacks
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04298—Processes for controlling fuel cells or fuel cell systems
- H01M8/04694—Processes for controlling fuel cells or fuel cell systems characterised by variables to be controlled
- H01M8/04858—Electric variables
- H01M8/04925—Power, energy, capacity or load
- H01M8/04947—Power, energy, capacity or load of auxiliary devices, e.g. batteries, capacitors
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04298—Processes for controlling fuel cells or fuel cell systems
- H01M8/04992—Processes for controlling fuel cells or fuel cell systems characterised by the implementation of mathematical or computational algorithms, e.g. feedback control loops, fuzzy logic, neural networks or artificial intelligence
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/34—Parallel operation in networks using both storage and other dc sources, e.g. providing buffering
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L2240/00—Control parameters of input or output; Target parameters
- B60L2240/40—Drive Train control parameters
- B60L2240/54—Drive Train control parameters related to batteries
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L2240/00—Control parameters of input or output; Target parameters
- B60L2240/60—Navigation input
- B60L2240/64—Road conditions
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L2240/00—Control parameters of input or output; Target parameters
- B60L2240/60—Navigation input
- B60L2240/66—Ambient conditions
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L2260/00—Operating Modes
- B60L2260/40—Control modes
- B60L2260/50—Control modes by future state prediction
- B60L2260/54—Energy consumption estimation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60Y—INDEXING SCHEME RELATING TO ASPECTS CROSS-CUTTING VEHICLE TECHNOLOGY
- B60Y2200/00—Type of vehicle
- B60Y2200/90—Vehicles comprising electric prime movers
- B60Y2200/91—Electric vehicles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60Y—INDEXING SCHEME RELATING TO ASPECTS CROSS-CUTTING VEHICLE TECHNOLOGY
- B60Y2400/00—Special features of vehicle units
- B60Y2400/20—Energy converters
- B60Y2400/202—Fuel cells
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/20—Pc systems
- G05B2219/26—Pc applications
- G05B2219/2668—Fuel cells
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M2250/00—Fuel cells for particular applications; Specific features of fuel cell system
- H01M2250/20—Fuel cells in motive systems, e.g. vehicle, ship, plane
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M2250/00—Fuel cells for particular applications; Specific features of fuel cell system
- H01M2250/40—Combination of fuel cells with other energy production systems
- H01M2250/402—Combination of fuel cell with other electric generators
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/50—Fuel cells
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/60—Other road transportation technologies with climate change mitigation effect
- Y02T10/72—Electric energy management in electromobility
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02T90/40—Application of hydrogen technology to transportation, e.g. using fuel cells
Definitions
- the invention will be described with respect to a truck, the invention is not restricted to this particular vehicle, but may also be used in other vehicles such as passenger cars and off-road vehicles.
- the invention may also be applied in vessels and in stationary applications, such as in grid-connected supplemental power generators or in grid-independent power generators.
- Fuel cell systems can be used as an alternative or as a complement to electric batteries for powering of electric vehicles, but also in stationary applications such as in grid-connected and grid-independent power generators.
- a primary object of the invention is to provide an in at least some aspect improved method for controlling a power assembly comprising a fuel cell unit and an electric energy storage system.
- it is an object to provide such a method which accounts for degradation of the fuel cell unit occurring in connection with start-up and shutdown of the fuel cell unit.
- the power assembly comprises a fuel cell unit and an electric energy storage system for storing excess electric energy produced by the fuel cell unit.
- the method which may be performed by a control unit of the power assembly, comprises:
- the power assembly may be operated with the fuel cell turned off during certain time periods.
- a time threshold By setting a time threshold and comparing the identified time period to the time threshold, it is possible to refrain from turning off the fuel cell unit during shorter time periods when such a mode of operation would not be desirable due to, for example, fuel cell degradation arising as a result of fuel cell shutdown and start-up.
- the fuel cell unit can be shut down only when the advantages of doing so, such as reduced fuel consumption and improved energy efficiency, outweigh the disadvantages, such as more rapid ageing of the fuel cell unit.
- the power assembly is expected to be able to deliver power in accordance with the power demand, or at least at the minimum power level.
- the minimum power level is herein set in relation to the predicted power demand.
- the power assembly may be able to deliver power in accordance with the power demand over a major portion of the time period, such as over 80% of the time period or more, such as over 90% of the time period, or preferably over the entire time period.
- a shorter time interval with a lower power may be accepted, as long as the lower power does not fall below the defined minimum power.
- the minimum power level may be set depending on performance requirements. For example, in a vehicle application, the minimum power level may be set such that the vehicle is able to travel at least at a predetermined vehicle speed.
- the power assembly By controlling the power assembly to shut down the fuel cell unit during at least a part of the identified time period, it is intended that the power assembly is operated with the fuel cell turned off during at least a part of the identified time period, such as during the entire identified time period, or during a portion of the identified time period starting at an identified suitable point in time for shutting down the fuel cell unit.
- the power assembly is operated either in a pure electric mode, i.e., using solely power from the electric energy storage system, or in a hybrid mode using solely power from the electric energy storage system and from another fuel cell of the power assembly.
- the power assembly may comprise more than one fuel cell units, in which case the fuel cell units may be controlled either independently or as a single system.
- the time period may be understood as the time period during which the power assembly can be operated with the fuel cell unit turned off without violating any power limit as defined by the predicted power demand and/or the minimum power level, and without violating any SoC limit of the electric energy storage system, hereinafter also referred to as the ESS.
- the SoC is a measure of the amount of energy available in the ESS at a specific point in time, usually expressed as a percentage of the amount of energy in the fully charged electric energy storage system.
- power capability refers to a charge and discharge capability of the ESS.
- the capability to charge and discharge the battery generally refers to a condition of the battery under ordinary use of the battery, such as in a vehicle.
- state-of-power, SoP is one example of an operational parameter indicative of the power capability of the ESS.
- the SoP of the ESS is defined by the maximum constant current magnitude or power magnitude with which the ESS can be continuously charged or discharged during the following time horizon of concern, i.e., the prediction time horizon, without violating any battery cell-level operating constraints.
- the SoP of the ESS may be determined in terms of one or both of current magnitude and power magnitude.
- the power or current that the ESS can actually deliver is dependent on the SoC of the ESS.
- the power capability increases with increasing SoC, such that a fully charged ESS can deliver a higher output power than an ESS with a relatively low SoC.
- the obtained SoC may be used to determine a maximum output power that may in turn be compared to the predicted power demand to determine whether the power assembly is expected to be able to deliver power in accordance with the predicted power demand with the fuel cell unit shut down.
- identifying the time period comprises identifying a first point in time at which a predetermined first criterion is fulfilled, and a second point in time at which a predetermined second criterion is fulfilled, wherein the first and second points in time are respective end points of the time period.
- the first criterion is herein a criterion for possible shutdown of the fuel cell unit
- the second criterion is a criterion for start-up of the fuel cell unit.
- the second point in time is subsequent to the first point in time.
- the predetermined first criterion is considered fulfilled when the predicted power demand is below a first power demand threshold, and optionally when the SoC is above a first SoC threshold and/or when a power capability of the electric energy storage system is above a first power capability threshold.
- a possible first point of the time period is identified.
- the SoC may herein be the SoC at the possible first point, i.e., a calculated SoC value is used, based on initial SoC and predicted power demand.
- the first SoC threshold may be set to be dependent on the first power demand threshold.
- predicting the power demand comprises predicting an instantaneous power demand as a function of time over the prediction time horizon, wherein identifying the time period comprises comparing the predicted instantaneous power demand to at least one power demand threshold.
- the predicted instantaneous power demand should in this case be lower than a power demand threshold in order to identify a possible first point of the time period.
- a second point of the time period is identified.
- the SoC of the ESS may also be taken into account to determine whether the first and second points of the time period are reached.
- predicting the power demand comprises determining an average power demand over at least a sub-range of the prediction time horizon, wherein identifying the time period comprises comparing the determined average power demand to at least one power demand threshold.
- the average power demand may be used in addition to the instantaneous power demand or as an alternative thereto.
- the power demand threshold that the average power demand is compared to may be different from, typically lower than, the power demand threshold that the instantaneous power demand is compared to.
- the SoC and/or power capability of the ESS may also be taken into account to determine whether the first and second points of the time period are reached.
- the method further comprises determining the time threshold based on at least one of an expected fuel cell degradation resulting from shutdown and start-up of the fuel cell unit, an expected efficiency loss of the power assembly during the time period, and an expected fuel saving during the time period.
- the time threshold can be set based on an expected ESS degradation occurring as a result of, e.g., charging the ESS above a maximum SoC limit, high ESS temperatures, or high current throughputs. Hence, the time threshold can be varied over the lifetime of the power assembly.
- control unit configured to perform the method according to the first aspect.
- the control unit may be an electronic control unit.
- FIG. 1 is a schematic side view of a vehicle
- FIG. 5 a - b are schematic block diagrams illustrating a control unit according to embodiments herein.
- FIG. 1 depicts a side view of a vehicle 100 according to an example embodiment of the invention.
- the vehicle 100 is here a truck, more specifically a heavy-duty truck for towing one or more trailers (not shown). Even though a heavy-duty truck 100 is shown it shall be noted that the invention is not limited to this type of vehicle but may be used for any other type of vehicle, such as a bus, construction equipment, e.g., a wheel loader and an excavator, and a passenger car. The invention is also applicable for other applications not relating to vehicles as long as a power assembly comprising a fuel cell unit and an electric energy storage system, ESS, are utilized.
- ESS electric energy storage system
- the vehicle 100 further comprises a control unit 5 according to an example embodiment of the invention.
- the control unit 5 is thus used for controlling the power assembly 1 .
- an on-board control unit 5 is shown, it shall be understood that the control unit 5 could also be a remote control unit 5 , i.e., an off-board control unit, or a combination of an on-board and off-board control unit.
- the control unit 5 may be configured to control the power assembly 1 by issuing control signals and by receiving status information relating to the power assembly 1 .
- the control unit 5 may form part of the power assembly 1 .
- the control unit 5 is an electronic control unit and may comprise processing circuitry which is adapted to run a computer program as disclosed herein.
- the control unit 5 may comprise hardware and/or software for performing the method according to the invention.
- the control unit 5 may be denoted a computer.
- the control unit 5 may be constituted by one or more separate sub-control units.
- the control unit 5 may communicate by use of wired and/or wireless communication means.
- FIG. 2 depicts a schematic illustration of a power assembly 1 according to an example embodiment of the invention.
- the power assembly 1 may for example be used in the vehicle 100 as shown in FIG. 1 .
- the power assembly 1 comprises at least one fuel cell unit, herein a first fuel cell unit 2 and a second fuel cell unit 3 .
- Each fuel cell unit 2 , 3 may comprise one or more fuel cells, typically several fuel cells.
- the fuel cells may also be denoted as a fuel cell stack, wherein the fuel cell stack may comprise several hundreds of fuel cells. Further, each fuel cell unit is arranged to provide the fuel cells with necessary supply of hydrogen fuel and air, cooling, etc.
- Each fuel cell unit 2 , 3 may comprise its own control system, which may be communicatively connected to the control unit 5 .
- the power assembly 1 in the illustrated embodiment comprises two fuel cell units 2 , 3 , it may alternatively comprise a single fuel cell unit, or more than two fuel cell units, such as three or more fuel cell units.
- the fuel cell units may be either independently controllable or commonly controllable.
- each fuel cell unit may be controlled to an on-state or an off-state regardless of the state(s) of the other fuel cell unit(s).
- those fuel cell units are controllable in common to an on-state or an off-state, i.e., all fuel cell units are controlled in common to the same state.
- Two fuel cell units may in some cases be controlled in dependence on one another, such that one of the fuel cell units is controlled to an on-state or an off-state in dependence on the state of the other fuel cell units.
- the power assembly 1 further comprise an ESS 4 , which may in turn comprise one or more batteries for storing excess electric energy produced by the fuel cell units 2 , 3 , as well as for providing output power from the power assembly 1 .
- the ESS 4 is electrically connected to the fuel cell units 2 , 3 .
- the ESS 4 may comprise its own control system, communicatively connected to the control unit 5 .
- the ESS 4 may further be used for storing energy regenerated during braking, and/or it may be configured for charging by a charger, such as from an external power grid.
- the power assembly 1 may further comprise power electronics (not shown) for converting electric power generated by the fuel cell units 2 , 3 and/or provided from the ESS 4 to electric power usable by a power consumer 6 , such as an electric motor or another power consumer. Further, in addition or alternative to what is mentioned in the above, the power assembly 1 may comprise various components such as compressors, sensors, pumps, valves, and electrical components.
- FIG. 3 depicts a method for controlling a power assembly, such as the power assembly 1 illustrated in FIG. 2 , according to an embodiment of the invention.
- a power assembly such as the power assembly 1 illustrated in FIG. 2
- FIGS. 4 a - 4 b illustrating two different exemplary operation scenarios.
- a power demand P for power delivery from the power assembly 1 over a prediction time horizon ⁇ t is predicted.
- the step S 1 of predicting the power demand P may comprise:
- the first step S 1 of predicting the power demand P may comprises predicting an instantaneous power demand P(t) as a function of time t over the prediction time horizon ⁇ t. It may alternatively, or additionally, comprise determining an average power demand P avg over at least a sub-range of the prediction time horizon ⁇ t.
- a state-of-charge, SoC, and/or a power capability, of the electric energy storage system 4 is obtained.
- An initial SoC value or power capability value such as a SoC or power capability of the ESS 4 at a time of predicting the power demand P, may be received from the control system of the ESS 4 , or it may be determined within the control unit 5 based on measurement data from the ESS 4 .
- the SoC and/or power capability of the ESS 4 as a function of time t over the prediction time horizon ⁇ t may be calculated in the control unit 5 as a function of the predicted power demand and a state of the fuel cell unit 2 , 3 .
- a time period ⁇ t within the prediction time horizon ⁇ t is predicted, during which time period ⁇ f the power assembly 1 is expected to be able to deliver power in accordance with the predicted power demand P with the fuel cell unit 2 , 3 shut down, or is at least expected to be able to deliver power at a minimum power level determined with respect to the predicted power demand P.
- the identified time period ⁇ t may, e.g., be a time period during which the power assembly 1 is expected to be able to deliver power in accordance with the predicted power demand P or at the minimum power level without violating a minimum SoC limit SoC min of the ESS 4 .
- the third step S 3 of identifying the time period ⁇ t may comprise identifying a first point in time t 1 , at which a predetermined first criterion is fulfilled, and a subsequent second point in time t 2 , at which a predetermined second criterion is fulfilled.
- the first and second points in time t 1 , t 2 are respective end points of the time period ⁇ t, wherein the first point in time t 1 defines a possible point in time at which a shutdown of the fuel cell unit 2 , 3 may be initiated, and wherein the second point in time t 2 may define a point in time at which a start-up of the fuel cell unit 2 , 3 must be, or is desirable to be, initiated.
- the predetermined first criterion may be set so that it is considered fulfilled at a point in time when the predicted power demand P is below a first power demand threshold, and optionally when the SoC is above a first SoC threshold SoC th1 , or when a power capability of the ESS 4 is above a first power capability threshold.
- the predetermined second criterion may be set so that it is considered fulfilled when start-up of the fuel cell unit 2 , 3 needs to be initiated again. This may be fulfilled when the predicted power demand P is above a second power demand threshold, and optionally when the SoC is below a second SoC threshold, such as minimum SoC limit SoC min of the ESS 4 , or when the power capability of the ESS 4 is below a second power capability threshold.
- the time period may be identified by comparing the predicted instantaneous power demand to at least one instantaneous power demand threshold.
- the time period may be identified by comparing the predicted instantaneous power demand to at least one average power demand threshold.
- a combination of instantaneous and average power demand thresholds may be applied.
- a fourth step S 4 the power assembly 1 is controlled to shut down the fuel cell unit 2 , 3 during at least a part of the identified time period ⁇ t in response to the identified time period ⁇ t being larger than a time threshold dt.
- the identified time period Ot is compared to the time threshold dt.
- the time threshold dt may be a predetermined fixed value, or it may be determined based on at least one of an expected fuel cell degradation resulting from shutdown and start-up of the fuel cell units 2 , 3 , an expected efficiency loss of the power assembly 1 during the time period ⁇ t, and an expected fuel saving during the time period ⁇ t.
- a relatively short time threshold dt may be set, while as if the expected fuel saving is small, a larger time threshold may be set.
- the time threshold can further be determined based on an expected ESS degradation.
- the step S 4 may comprise initiating shutdown of the fuel cell unit 2 , 3 at the first point in time t 1 identified as a starting point of the time period ⁇ t.
- the power assembly 1 may thereafter be controlled to either operate with the fuel cell unit 2 , 3 shut down during the entire identified time period ⁇ t or longer, or to turn on the fuel cell unit 2 , 3 again depending on an outcome of an updated prediction at a later point in time.
- the predicted power demand P may be below the second power demand threshold, and the SoC and/or the power capability may be expected to stay above the respective second thresholds during the entire prediction time horizon ⁇ t remaining after the first point in time t 1 .
- the identified time period Ot is larger than the time threshold dt, without actually having identified the second point in time.
- the time threshold dt may herein be set to a value which is specific for each one of the two or more fuel cell units 2 , 3 . For example, if the fuel cell units 2 , 3 are different in behaviour and in size, the degradation arising at shutdown and start-up will differ. The time threshold dt may be set by taking such differences into account.
- FIG. 4 a schematically illustrates a first exemplary operation scenario of the power assembly 1 .
- the upper diagram of FIG. 4 a illustrates power demand P as a function of time t for a power assembly 1
- the lower diagram illustrates expected SoC of the ESS 4 of the power assembly 1 as a function of time t.
- the instantaneous power demand P(t) of the power assembly 1 illustrated by a solid line, is initially predicted over the prediction time horizon ⁇ t.
- An average power demand P avg over the prediction time horizon ⁇ t is also determined, as illustrated by a dashed line.
- a first point in time t 1 is identified at which the average predicted power demand P avg and the instantaneous predicted power demand P(t) are below a first power demand threshold P th1 and a second power demand threshold P th2 , respectively, and at which the SoC is above a first SoC threshold level SoC th1 .
- a predetermined first criterion is thereby considered fulfilled and the first point in time t 1 is identified as a possible time for shutting down the fuel cell units 2 , 3 , and consequently as a starting point for a time period ⁇ t during which it may be possible to operate the power assembly 1 with the fuel cell units 2 , 3 turned off.
- the expected SoC development after a possible shutdown of the fuel cell units 2 , 3 at the first point in time t 1 is illustrated as a dashed line SoC 2 , while the solid line SoC 1 illustrates the SoC development under the assumption that the fuel cell units 2 , 3 remain turned on.
- the time period ⁇ t is compared to a time threshold dt and since it is found that the time period ⁇ t is larger than the time threshold dt, the power assembly 1 may be controlled to shut down the fuel cell units 2 , 3 at the first point in time t 1 .
- Start-up of the fuel cell units 2 , 3 may be planned at the second point in time t 2 , but the start-up may be postponed or advanced depending on the, for example, unexpected events not accounted for in the initial prediction.
- the prediction is preferably updated continuously to identify such unexpected changes.
- control unit 5 may be configured to perform any one or more of the above steps S 1 -S 4 , and/or any other examples or embodiments herein.
- the control unit 5 may for example comprise an arrangement as depicted in FIGS. 5 a and 5 b.
- the control unit 5 may further be arranged to, by means of an obtaining unit 502 , obtain at least one of a state-of-charge, SoC, and a power capability of the electric energy storage system 4 .
- the control unit 5 is further arranged to, by means of a controlling unit 504 , control the power assembly 1 to shut down the fuel cell unit 2 , 3 during the identified time period ⁇ t in response to the identified time period ⁇ t being larger than a time threshold dt.
- the method described herein may be implemented through a processor or one or more processors, such as the processor 560 of a processing circuitry in the control unit 5 depicted in FIG. 5 a , together with computer program code for performing the functions and actions of the embodiments herein.
- the program code mentioned above may also be provided as a computer program medium, for instance in the form of a data computer readable medium carrying computer program code for performing the method steps described herein when being loaded into the control unit 5 .
- One such computer readable medium may be in the form of a memory stick.
- the computer program code may furthermore be provided as pure program code on a server and downloaded to the control unit 5 .
- the control unit 5 may further comprise a memory 570 comprising one or more memory units.
- the memory 570 comprises instructions executable by the processor in control unit 5 .
- the memory 570 is arranged to be used to store, e.g., information, data, control scenarios, costs, etc. to perform the methods herein when being executed in the control unit 5 .
- a computer-readable storage medium 590 comprises the respective computer program 580 .
- the computer-readable storage medium 590 may comprise program code for performing the method steps described above when said program product is run on a computer, e.g., the at least one processor 560 .
- control unit 5 may refer to a combination of analogue and digital circuits, and/or one or more processors configured with software and/or firmware, e.g., stored in the control unit 5 , that when executed by the respective one or more processors such as the processors described above.
- processors as well as the other digital hardware, may be included in a single Application-Specific Integrated Circuitry (ASIC), or several processors and various digital hardware may be distributed among several separate components, whether individually packaged or assembled into a system-on-a-chip.
- ASIC Application-Specific Integrated Circuitry
Landscapes
- Engineering & Computer Science (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Power Engineering (AREA)
- General Chemical & Material Sciences (AREA)
- Transportation (AREA)
- Mechanical Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Manufacturing & Machinery (AREA)
- Automation & Control Theory (AREA)
- Health & Medical Sciences (AREA)
- Artificial Intelligence (AREA)
- Computing Systems (AREA)
- Evolutionary Computation (AREA)
- Fuzzy Systems (AREA)
- Medical Informatics (AREA)
- Software Systems (AREA)
- Theoretical Computer Science (AREA)
- Combustion & Propulsion (AREA)
- Fuel Cell (AREA)
- Supply And Distribution Of Alternating Current (AREA)
Abstract
A method for controlling a power assembly comprising a fuel cell unit and an electric energy storage system for storing excess electric energy produced by the fuel cell unit. The method comprises predicting a power demand from the power assembly over a prediction time horizon, obtaining a state-of-charge and/or power capability of the electric energy storage system, based on the predicted power demand and the obtained SoC and/or power capability, identifying a time period during which the power assembly is expected to be able to deliver power in accordance with the predicted power demand with the fuel cell unit shut down, or is at least expected to be able to deliver power at a minimum power level determined with respect to the predicted power demand, controlling the power assembly to shut down the fuel cell unit during at least a part of the identified time period in response to the identified time period being larger than a time threshold.
Description
- The invention relates to a method for controlling a power assembly comprising one or more fuel cell units and an electric energy storage system. It further relates to a power assembly, a control unit, a vehicle, a computer program, and a computer readable medium.
- Although the invention will be described with respect to a truck, the invention is not restricted to this particular vehicle, but may also be used in other vehicles such as passenger cars and off-road vehicles. The invention may also be applied in vessels and in stationary applications, such as in grid-connected supplemental power generators or in grid-independent power generators.
- Fuel cell systems can be used as an alternative or as a complement to electric batteries for powering of electric vehicles, but also in stationary applications such as in grid-connected and grid-independent power generators.
- When a fuel cell system operates at low current densities, the polarisation cell voltage of the fuel cells increases, which in turn has a negative impact on the durability of the fuel cells. To save the fuel cells from degradation, an operational maximum polarisation cell voltage is set, meaning in practice that the lowest operational power of the fuel cells is limited. In certain situations, such as when a vehicle powered by the fuel cell system travels downhill, the fuel cell system may therefore be operated at a higher power than necessary in view of a power demand of the vehicle. Excess power generated by the fuel cell system may in that case be stored in a battery. However, when the battery has reached its maximum state-of-charge, SoC, power generated by the fuel cell system may instead be dissipated and thereby wasted.
- In order to avoid energy dissipation, control strategies exist according to which the fuel cell system is turned off when the SoC of the battery is relatively high and the power demand is low. US20160046204 discloses such a method for controlling a fuel cell system of a vehicle, wherein the fuel cell is controlled to be on or off depending on a predicted power need of the vehicle and the SoC of a battery. However, turning the fuel cell on and off is associated with degradation of the fuel cell, reducing its service life.
- A primary object of the invention is to provide an in at least some aspect improved method for controlling a power assembly comprising a fuel cell unit and an electric energy storage system. In particular, it is an object to provide such a method which accounts for degradation of the fuel cell unit occurring in connection with start-up and shutdown of the fuel cell unit.
- Thus, a method for controlling a power assembly is provided. The power assembly comprises a fuel cell unit and an electric energy storage system for storing excess electric energy produced by the fuel cell unit. The method, which may be performed by a control unit of the power assembly, comprises:
-
- predicting a power demand for power delivery from the power assembly over a prediction time horizon,
- obtaining at least one of a state-of-charge, SoC, and a power capability of the electric energy storage system,
- based on the predicted power demand and the obtained SoC and/or power capability, identifying a time period within the prediction time horizon, during which time period the power assembly is expected to be able to deliver power in accordance with the predicted power demand with the fuel cell unit shut down, or is at least expected to be able to deliver power at a minimum power level determined with respect to the predicted power demand,
- controlling the power assembly to shut down the fuel cell unit during at least a part of the identified time period in response to the identified time period being larger than a time threshold.
- Hence, according to the invention, the power assembly may be operated with the fuel cell turned off during certain time periods. By setting a time threshold and comparing the identified time period to the time threshold, it is possible to refrain from turning off the fuel cell unit during shorter time periods when such a mode of operation would not be desirable due to, for example, fuel cell degradation arising as a result of fuel cell shutdown and start-up. Instead, the fuel cell unit can be shut down only when the advantages of doing so, such as reduced fuel consumption and improved energy efficiency, outweigh the disadvantages, such as more rapid ageing of the fuel cell unit.
- During the time period, the power assembly is expected to be able to deliver power in accordance with the power demand, or at least at the minimum power level. The minimum power level is herein set in relation to the predicted power demand. Typically, the power assembly may be able to deliver power in accordance with the power demand over a major portion of the time period, such as over 80% of the time period or more, such as over 90% of the time period, or preferably over the entire time period. Hence, a shorter time interval with a lower power may be accepted, as long as the lower power does not fall below the defined minimum power. The minimum power level may be set depending on performance requirements. For example, in a vehicle application, the minimum power level may be set such that the vehicle is able to travel at least at a predetermined vehicle speed.
- By controlling the power assembly to shut down the fuel cell unit during at least a part of the identified time period, it is intended that the power assembly is operated with the fuel cell turned off during at least a part of the identified time period, such as during the entire identified time period, or during a portion of the identified time period starting at an identified suitable point in time for shutting down the fuel cell unit. Hence, during at least a part of the time period, the power assembly is operated either in a pure electric mode, i.e., using solely power from the electric energy storage system, or in a hybrid mode using solely power from the electric energy storage system and from another fuel cell of the power assembly. The power assembly may comprise more than one fuel cell units, in which case the fuel cell units may be controlled either independently or as a single system.
- The time period may be understood as the time period during which the power assembly can be operated with the fuel cell unit turned off without violating any power limit as defined by the predicted power demand and/or the minimum power level, and without violating any SoC limit of the electric energy storage system, hereinafter also referred to as the ESS. The SoC is a measure of the amount of energy available in the ESS at a specific point in time, usually expressed as a percentage of the amount of energy in the fully charged electric energy storage system.
- The term “power capability” as used herein refers to a charge and discharge capability of the ESS. For example, the term “power capability”, as used herein, typically refers to a charge and discharge capability of a battery within the ESS. The capability to charge and discharge the battery generally refers to a condition of the battery under ordinary use of the battery, such as in a vehicle. For example, state-of-power, SoP, is one example of an operational parameter indicative of the power capability of the ESS. The SoP of the ESS is defined by the maximum constant current magnitude or power magnitude with which the ESS can be continuously charged or discharged during the following time horizon of concern, i.e., the prediction time horizon, without violating any battery cell-level operating constraints. The SoP of the ESS may be determined in terms of one or both of current magnitude and power magnitude.
- When the fuel cell unit has been turned off, the SoC of the ESS will decrease over time as energy from the ESS is consumed. The evolution of the SoC value over time is a function of the initial SoC and the power demand. Thus, the SoC value as a function of time over the prediction horizon may be calculated from the predicted power demand and the initial SoC of the ESS, which may, purely by way of example, be estimated from measured open circuit voltage (OCV) of the ESS and/or determined using Coulomb counting. Obtaining the SoC of the ESS may thus comprise calculating the SoC as a function of time based on the initially obtained SoC and the predicted power demand. The initial SoC value may be received from a control system of the ESS, such as a battery management unit or similar, or calculated based on measurement data received from the ESS.
- The power or current that the ESS can actually deliver is dependent on the SoC of the ESS. The power capability increases with increasing SoC, such that a fully charged ESS can deliver a higher output power than an ESS with a relatively low SoC. Hence, when the maximum output power of the ESS as a function of SoC is known, the obtained SoC may be used to determine a maximum output power that may in turn be compared to the predicted power demand to determine whether the power assembly is expected to be able to deliver power in accordance with the predicted power demand with the fuel cell unit shut down.
- When the identified time period is shorter than the time threshold, the fuel cell unit remains turned on.
- Optionally, the identified time period is a time period during which the power assembly is expected to be able to deliver power in accordance with the predicted power demand or at the minimum power level without violating a minimum SoC limit of the electric energy storage system. The minimum SoC limit may be a predetermined limit. The minimum SoC limit may vary with age of the ESS such that at the beginning of life of an ESS, the minimum SoC limit is set to a lower value than when the ESS becomes aged.
- Optionally, identifying the time period comprises comparing the predicted power demand to at least one power demand threshold.
- Optionally, identifying the time period further comprises comparing the obtained SoC to at least one SoC threshold and/or comparing the power capability to at least one power capability threshold. Hence, identifying the time period may comprise determining a maximum possible output power, or current, from the ESS and comparing the maximum possible output power, or current, to at least one power threshold.
- Optionally, identifying the time period comprises identifying a first point in time at which a predetermined first criterion is fulfilled, and a second point in time at which a predetermined second criterion is fulfilled, wherein the first and second points in time are respective end points of the time period. The first criterion is herein a criterion for possible shutdown of the fuel cell unit, and the second criterion is a criterion for start-up of the fuel cell unit. The second point in time is subsequent to the first point in time.
- Optionally, the predetermined first criterion is considered fulfilled when the predicted power demand is below a first power demand threshold, and optionally when the SoC is above a first SoC threshold and/or when a power capability of the electric energy storage system is above a first power capability threshold. Hence, when the predicted power demand is below the first power demand threshold, and optionally when the SoC/power capability is above the first SoC/power capability threshold, a possible first point of the time period is identified. The SoC may herein be the SoC at the possible first point, i.e., a calculated SoC value is used, based on initial SoC and predicted power demand. The first SoC threshold may be set to be dependent on the first power demand threshold. Instead of comparing the SoC to a first SoC threshold, the SoC may be used to determine the power capability of the ESS, which power capability is in turn compared to a first power capability threshold. The power capability may alternatively be obtained in other ways, without using SoC.
- Optionally, the predetermined second criterion is considered fulfilled when the predicted power demand is above a second power demand threshold, and optionally when the SoC is below a second SoC threshold and/or when the power capability is below a second power capability threshold. Hence, when the predicted power demand is above the second power demand threshold, and optionally when the SoC/power capability is below the second SoC/power capability threshold, a second point of the time period is identified, at which it will be necessary to start the fuel cell unit again in order not to violate SoC and/or power limits of the power assembly. The SoC may be the calculated SoC at the second point of the time period. The second SoC threshold may be set to be dependent on the second power demand threshold. Instead of comparing the SoC to a second SoC threshold, the SoC may be used to determine a power capability of the ESS, which power capability is in turn compared to a second power capability threshold. The power capability may alternatively be obtained in other ways, without using SoC.
- The predetermined second criterion may also be considered fulfilled when, during the entire prediction time horizon remaining after the first point in time, the predicted power demand stays below the second power demand threshold, and optionally when the SoC stays below the second SoC threshold and/or when the power capability stays below the second power capability threshold. In this case, the second point in time is unknown and the identified time period may be determined to be larger than the time threshold.
- Optionally, predicting the power demand comprises predicting an instantaneous power demand as a function of time over the prediction time horizon, wherein identifying the time period comprises comparing the predicted instantaneous power demand to at least one power demand threshold. The predicted instantaneous power demand should in this case be lower than a power demand threshold in order to identify a possible first point of the time period. Once the predicted instantaneous power demand is above the power demand threshold, a second point of the time period is identified. Of course, the SoC of the ESS may also be taken into account to determine whether the first and second points of the time period are reached.
- Optionally, predicting the power demand comprises determining an average power demand over at least a sub-range of the prediction time horizon, wherein identifying the time period comprises comparing the determined average power demand to at least one power demand threshold. The average power demand may be used in addition to the instantaneous power demand or as an alternative thereto. The power demand threshold that the average power demand is compared to may be different from, typically lower than, the power demand threshold that the instantaneous power demand is compared to. Of course, the SoC and/or power capability of the ESS may also be taken into account to determine whether the first and second points of the time period are reached.
- Optionally, the time threshold is a predetermined fixed value. The predetermined fixed value may be set taking fuel cell degradation resulting from shutdown and start-up of the at least one fuel cell unit, efficiency loss of the power assembly during the time period and expected fuel saving during the time period into account. Also, ESS degradation occurring as a result of, e.g., charging the ESS above a maximum SoC limit may be taken into account.
- Optionally, the method further comprises determining the time threshold based on at least one of an expected fuel cell degradation resulting from shutdown and start-up of the fuel cell unit, an expected efficiency loss of the power assembly during the time period, and an expected fuel saving during the time period. Additionally, the time threshold can be set based on an expected ESS degradation occurring as a result of, e.g., charging the ESS above a maximum SoC limit, high ESS temperatures, or high current throughputs. Hence, the time threshold can be varied over the lifetime of the power assembly.
- Optionally, the power assembly comprises two or more fuel cell units, and identifying the time period comprises identifying a time period during which the power assembly is expected to be able to deliver power in accordance with the power demand with at least one of the at least two fuel cell units shut down, and wherein, in response to the identified time period being larger than the time threshold, said at least one fuel cell unit is scheduled to be shut down during at least a part of the identified time period. Hence, some or all of the fuel cell units may be shut down during the identified time period. The fuel cell unit(s) may not need to be turned on again after the identified time period. Furthermore, if something unexpected happens, the fuel cell unit(s) may be turned on again during the identified time period.
- Optionally, the time threshold is set to a value which is specific for each one of the two or more fuel cell units. This may be relevant when the two or more fuel cell systems are of different types, configurations, sizes, and/or ages, since the degradation of the fuel cell units arising at start-up and shutdown as well as during operation differs depending on those factors. The threshold time is set to a value above which the cost for shutting down the fuel cell becomes lower than the cost for keeping it turned on.
- Optionally, the power assembly is adapted to deliver power contributing to the propulsion of a vehicle, and wherein predicting the power demand comprises:
-
- receiving vehicle related information comprising at least one of traffic information for an expected travelling route of the vehicle during the prediction time horizon, terrain information for the expected travelling route, topographic information for the expected travelling route during the prediction time horizon, weather information for the expected travelling route during the prediction time horizon, and vehicle gross weight information, and
- using said received vehicle related information for predicting the power demand over the prediction time horizon.
- One or more of the above vehicle related pieces of information can contribute to a proper prediction of the power demand.
- According to a second aspect of the invention, a control unit configured to perform the method according to the first aspect is provided. The control unit may be an electronic control unit.
- Advantages and effects of the second aspect of the invention are largely analogous to the advantages and effects of the first aspect of the invention.
- According to a third aspect of the invention, a power assembly comprises one or more fuel cell units and an electric energy storage system for storing excess electric energy produced by the one or more fuel cell units. The power assembly further comprises the control unit according to the second aspect.
- According to a fourth aspect of the invention, a vehicle comprises a power assembly according to the third aspect, wherein the power assembly is adapted to deliver power contributing to the propulsion of the vehicle. The power assembly may be configured to deliver power in accordance with a power request received from a control unit of the vehicle.
- According to a fifth aspect of the invention, a computer program comprising program code means for performing the method of the first aspect when the program is run on a computer is provided.
- According to a sixth aspect of the invention, a computer readable medium carrying a computer program comprising program code means for performing the method of the first aspect when the program is run on a computer is provided.
- Further advantages and advantageous features of the invention are disclosed in the following description and in the dependent claims.
- With reference to the appended drawings, below follows a more detailed description of embodiments of the invention cited as examples.
- In the drawings:
-
FIG. 1 is a schematic side view of a vehicle; -
FIG. 2 is a schematic view of a power assembly according to an example embodiment of the invention; -
FIG. 3 is a flow chart illustrating an embodiment of the method of the present invention, -
FIG. 4 a-b illustrates predicted power demand as a function of time over a prediction horizon, and -
FIG. 5 a-b are schematic block diagrams illustrating a control unit according to embodiments herein. - With reference to the appended drawings, below follows a more detailed description of embodiments of the invention cited as examples.
-
FIG. 1 depicts a side view of avehicle 100 according to an example embodiment of the invention. Thevehicle 100 is here a truck, more specifically a heavy-duty truck for towing one or more trailers (not shown). Even though a heavy-duty truck 100 is shown it shall be noted that the invention is not limited to this type of vehicle but may be used for any other type of vehicle, such as a bus, construction equipment, e.g., a wheel loader and an excavator, and a passenger car. The invention is also applicable for other applications not relating to vehicles as long as a power assembly comprising a fuel cell unit and an electric energy storage system, ESS, are utilized. - The
vehicle 100 comprises apower assembly 1 according to an example embodiment of the invention. Thepower assembly 1 is here used for powering one or more electric motors (not shown) which are used for creating a propulsion force to thevehicle 100. Thepower assembly 1 may additionally or alternatively be used for powering other electric power consumers of the vehicle, such as an electric motor for a refrigerator system, an electric motor for an air conditioning system or any other electric power consuming function of thevehicle 100. - The
vehicle 100 further comprises acontrol unit 5 according to an example embodiment of the invention. Thecontrol unit 5 is thus used for controlling thepower assembly 1. Even though an on-board control unit 5 is shown, it shall be understood that thecontrol unit 5 could also be aremote control unit 5, i.e., an off-board control unit, or a combination of an on-board and off-board control unit. Thecontrol unit 5 may be configured to control thepower assembly 1 by issuing control signals and by receiving status information relating to thepower assembly 1. Thecontrol unit 5 may form part of thepower assembly 1. - The
control unit 5 is an electronic control unit and may comprise processing circuitry which is adapted to run a computer program as disclosed herein. Thecontrol unit 5 may comprise hardware and/or software for performing the method according to the invention. In an embodiment thecontrol unit 5 may be denoted a computer. Thecontrol unit 5 may be constituted by one or more separate sub-control units. In addition, thecontrol unit 5 may communicate by use of wired and/or wireless communication means. -
FIG. 2 depicts a schematic illustration of apower assembly 1 according to an example embodiment of the invention. Thepower assembly 1 may for example be used in thevehicle 100 as shown inFIG. 1 . - The
power assembly 1 comprises at least one fuel cell unit, herein a firstfuel cell unit 2 and a secondfuel cell unit 3. Eachfuel cell unit fuel cell unit control unit 5. Although thepower assembly 1 in the illustrated embodiment comprises twofuel cell units - The
power assembly 1 further comprise anESS 4, which may in turn comprise one or more batteries for storing excess electric energy produced by thefuel cell units power assembly 1. TheESS 4 is electrically connected to thefuel cell units ESS 4 may comprise its own control system, communicatively connected to thecontrol unit 5. TheESS 4 may further be used for storing energy regenerated during braking, and/or it may be configured for charging by a charger, such as from an external power grid. - The
power assembly 1 may further comprise power electronics (not shown) for converting electric power generated by thefuel cell units ESS 4 to electric power usable by apower consumer 6, such as an electric motor or another power consumer. Further, in addition or alternative to what is mentioned in the above, thepower assembly 1 may comprise various components such as compressors, sensors, pumps, valves, and electrical components. -
FIG. 3 depicts a method for controlling a power assembly, such as thepower assembly 1 illustrated inFIG. 2 , according to an embodiment of the invention. Reference is also made toFIGS. 4 a-4 b , illustrating two different exemplary operation scenarios. - In a first step S1, a power demand P for power delivery from the
power assembly 1 over a prediction time horizon Δt is predicted. When thepower assembly 1 is adapted to deliver power contributing to the propulsion of avehicle 100, the step S1 of predicting the power demand P may comprise: -
- receiving vehicle related information comprising at least one of traffic information for an expected travelling route of the
vehicle 100 during the prediction horizon Δt, terrain information for the expected travelling route, topographic information for the expected travelling route during the prediction horizon Δt, weather information for the expected travelling route during the prediction horizon Δt, and vehicle gross weight information, and - using said received vehicle related information for predicting the power demand P over the prediction horizon Δt.
- receiving vehicle related information comprising at least one of traffic information for an expected travelling route of the
- The first step S1 of predicting the power demand P may comprises predicting an instantaneous power demand P(t) as a function of time t over the prediction time horizon Δt. It may alternatively, or additionally, comprise determining an average power demand Pavg over at least a sub-range of the prediction time horizon Δt.
- In a second step S2, a state-of-charge, SoC, and/or a power capability, of the electric
energy storage system 4 is obtained. An initial SoC value or power capability value, such as a SoC or power capability of theESS 4 at a time of predicting the power demand P, may be received from the control system of theESS 4, or it may be determined within thecontrol unit 5 based on measurement data from theESS 4. The SoC and/or power capability of theESS 4 as a function of time t over the prediction time horizon Δt may be calculated in thecontrol unit 5 as a function of the predicted power demand and a state of thefuel cell unit - In a third step S3, based on the predicted power demand P and the obtained SoC and/or power capability, a time period δt within the prediction time horizon Δt is predicted, during which time period δf the
power assembly 1 is expected to be able to deliver power in accordance with the predicted power demand P with thefuel cell unit power assembly 1 is expected to be able to deliver power in accordance with the predicted power demand P or at the minimum power level without violating a minimum SoC limit SoCmin of theESS 4. - The third step S3 of identifying the time period δt may comprise identifying a first point in time t1, at which a predetermined first criterion is fulfilled, and a subsequent second point in time t2, at which a predetermined second criterion is fulfilled. The first and second points in time t1, t2 are respective end points of the time period δt, wherein the first point in time t1 defines a possible point in time at which a shutdown of the
fuel cell unit fuel cell unit ESS 4 is above a first power capability threshold. - The predetermined second criterion may be set so that it is considered fulfilled when start-up of the
fuel cell unit ESS 4, or when the power capability of theESS 4 is below a second power capability threshold. - When the instantaneous power demand has been predicted in the first step S1, the time period may be identified by comparing the predicted instantaneous power demand to at least one instantaneous power demand threshold. When the average power demand has been determined in the first step S1, the time period may be identified by comparing the predicted instantaneous power demand to at least one average power demand threshold. A combination of instantaneous and average power demand thresholds may be applied.
- In a fourth step S4, the
power assembly 1 is controlled to shut down thefuel cell unit fuel cell units power assembly 1 during the time period δt, and an expected fuel saving during the time period δt. For example, if the expected fuel saving arising due to fuel cell unit shutdown is relatively large, a relatively short time threshold dt may be set, while as if the expected fuel saving is small, a larger time threshold may be set. The time threshold can further be determined based on an expected ESS degradation. The step S4 may comprise initiating shutdown of thefuel cell unit power assembly 1 may thereafter be controlled to either operate with thefuel cell unit fuel cell unit - In some cases, the predicted power demand P may be below the second power demand threshold, and the SoC and/or the power capability may be expected to stay above the respective second thresholds during the entire prediction time horizon Δt remaining after the first point in time t1. In such cases, a point in time at which it will be necessary to start up the
fuel cell units - When the
power assembly 1 comprises two or morefuel cell units power assembly 1 is expected to be able to deliver power in accordance with the power demand P with at least one of the at least twofuel cell units fuel cell units power assembly 1 may during the time period δt be operated with onefuel cell unit fuel cell units fuel cell units -
FIG. 4 a schematically illustrates a first exemplary operation scenario of thepower assembly 1. The upper diagram ofFIG. 4 a illustrates power demand P as a function of time t for apower assembly 1, and the lower diagram illustrates expected SoC of theESS 4 of thepower assembly 1 as a function of time t. At a time t0, the instantaneous power demand P(t) of thepower assembly 1, illustrated by a solid line, is initially predicted over the prediction time horizon Δt. An average power demand Pavg over the prediction time horizon Δt is also determined, as illustrated by a dashed line. - In the first exemplary operation scenario, a first point in time t1 is identified at which the average predicted power demand Pavg and the instantaneous predicted power demand P(t) are below a first power demand threshold Pth1 and a second power demand threshold Pth2, respectively, and at which the SoC is above a first SoC threshold level SoCth1. A predetermined first criterion is thereby considered fulfilled and the first point in time t1 is identified as a possible time for shutting down the
fuel cell units power assembly 1 with thefuel cell units fuel cell units fuel cell units - As can be seen in the upper diagram, it the
fuel cell units fuel cell units - The time period δt is compared to a time threshold dt and since it is found that the time period δt is larger than the time threshold dt, the
power assembly 1 may be controlled to shut down thefuel cell units fuel cell units -
FIG. 4 b schematically illustrates a second exemplary operation scenario of thepower assembly 1. The same annotations are used as in the first exemplary operation scenario illustrated inFIG. 4 a , and the first point in time t1 is identified as described above with reference toFIG. 4 a . However, in the second operation scenario, the predicted instantaneous power demand P(t) increases above the second power demand threshold Pth2 at the second point in time t2, just before a point in time at which the SoC value, illustrated by the dashed line SoC2, is expected to fall below the minimum SoC limit SoCmin. Hence, the second point in time t2 is identified as an end point of the time period δt, at which start-up of thefuel cell units power assembly 1 will in this case be controlled to keep thefuel cell units - To perform the method steps described herein, the
control unit 5 may be configured to perform any one or more of the above steps S1-S4, and/or any other examples or embodiments herein. Thecontrol unit 5 may for example comprise an arrangement as depicted inFIGS. 5 a and 5 b. - The
control unit 5 may comprise an input andoutput interface 500 configured to communicate with any necessary components and/or entities of embodiments herein, e.g., to receive system states from theESS 4, to receive traffic information, terrain information, topographic information, weather information, and vehicle gross weight information. The input andoutput interface 500 may comprise a wireless and/or wired receiver (not shown) and a wireless and/or wired transmitter (not shown). Thecontrol unit 5 may be arranged in any suitable location of thevehicle 100. Thecontrol unit 5 may use the input andoutput interface 500 to control and communicate with sensors, actuators, subsystems, and interfaces in thevehicle 100 by using any one or more out of a Controller Area Network (CAN), ethernet cables, Wi-Fi, Bluetooth, and other network interfaces. - The
control unit 5 is arranged to, by means of a predictingunit 501, predict the power demand for power delivery from thepower assembly 1 over the prediction time horizon based on data received via theinterface 500. - The
control unit 5 may further be arranged to, by means of an obtainingunit 502, obtain at least one of a state-of-charge, SoC, and a power capability of the electricenergy storage system 4. - The
control unit 5 is further arranged to, by means of an identifyingunit 503, identify a time period δt within the prediction time horizon Δt during which thepower assembly 1 is expected to be able to deliver power in accordance with the predicted power demand with thefuel cell unit unit 503 is configured to identify the time period δt based on the predicted power demand and the obtained SoC and/or power capability. - The
control unit 5 is further arranged to, by means of a controllingunit 504, control thepower assembly 1 to shut down thefuel cell unit - The method described herein may be implemented through a processor or one or more processors, such as the
processor 560 of a processing circuitry in thecontrol unit 5 depicted inFIG. 5 a , together with computer program code for performing the functions and actions of the embodiments herein. The program code mentioned above may also be provided as a computer program medium, for instance in the form of a data computer readable medium carrying computer program code for performing the method steps described herein when being loaded into thecontrol unit 5. One such computer readable medium may be in the form of a memory stick. The computer program code may furthermore be provided as pure program code on a server and downloaded to thecontrol unit 5. - The
control unit 5 may further comprise amemory 570 comprising one or more memory units. Thememory 570 comprises instructions executable by the processor incontrol unit 5. Thememory 570 is arranged to be used to store, e.g., information, data, control scenarios, costs, etc. to perform the methods herein when being executed in thecontrol unit 5. - In some embodiments, a
computer program 580 comprises instructions, which when executed by a computer, e.g., the at least oneprocessor 560, cause the at least one processor of thecontrol unit 5 to perform the method steps described above. - In some embodiments, a computer-
readable storage medium 590 comprises therespective computer program 580. The computer-readable storage medium 590 may comprise program code for performing the method steps described above when said program product is run on a computer, e.g., the at least oneprocessor 560. - Those skilled in the art will appreciate that the units in the
control unit 5 described above may refer to a combination of analogue and digital circuits, and/or one or more processors configured with software and/or firmware, e.g., stored in thecontrol unit 5, that when executed by the respective one or more processors such as the processors described above. One or more of these processors, as well as the other digital hardware, may be included in a single Application-Specific Integrated Circuitry (ASIC), or several processors and various digital hardware may be distributed among several separate components, whether individually packaged or assembled into a system-on-a-chip. - It is to be understood that the present invention is not limited to the embodiments described above and illustrated in the drawings; rather, the skilled person will recognize that many changes and modifications may be made within the scope of the appended claims.
Claims (17)
1. A method for controlling a power assembly, the power assembly comprising a fuel cell unit and an electric energy storage system for storing excess electric energy produced by the fuel cell unit, the method comprising:
predicting a power demand for power delivery from the power assembly over a prediction time horizon,
obtaining at least one of a state-of-charge, SoC, and a power capability of the electric energy storage system,
based on the predicted power demand and the obtained SoC and/or power capability, identifying a time period within the prediction time horizon, during which time period the power assembly is expected to be able to deliver power in accordance with the predicted power demand with the fuel cell unit shut down, or is at least expected to be able to deliver power at a minimum power level determined with respect to the predicted power demand,
controlling the power assembly to shut down the fuel cell unit during at least a part of the identified time period in response to the identified time period being larger than a time threshold.
2. The method according to claim 1 , wherein the identified time period is a time period during which the power assembly is expected to be able to deliver power in accordance with the predicted power demand or at the minimum power level without violating a minimum SoC limit of the electric energy storage system.
3. The method according to claim 1 , wherein identifying the time period comprises:
comparing the predicted power demand to at least one power demand threshold, and optionally
comparing the obtained SoC to at least one SoC threshold, and/or comparing the power capability to at least one power capability threshold.
4. The method according to claim 1 , wherein identifying the time period comprises identifying a first point in time at which a predetermined first criterion is fulfilled, and a second point in time at which a predetermined second criterion is fulfilled, wherein the first and second points in time are respective end points of the time period.
5. The method according to claim 4 , wherein the predetermined first criterion is considered fulfilled when the predicted power demand is below a first power demand threshold, and optionally when the SoC is above a first SoC threshold and/or when the power capability is above a first power capability threshold.
6. The method according to claim 4 , wherein the predetermined second criterion is considered fulfilled when the predicted power demand is above a second power demand threshold, and optionally when the SoC is below a second SoC threshold and/or when the power capability is below a second power capability threshold.
7. The method according to claim 1 , wherein predicting the power demand comprises predicting an instantaneous power demand as a function of time over the prediction time horizon, and wherein identifying the time period comprises comparing the predicted instantaneous power demand to at least one power demand threshold.
8. The method according to claim 1 , wherein predicting the power demand comprises determining an average power demand over at least a sub-range of the prediction time horizon, and wherein identifying the time period comprises comparing the determined average power demand to at least one power demand threshold.
9. The method according to claim 1 , wherein the time threshold is a predetermined fixed value, or wherein the method further comprises determining the time threshold based on at least one of an expected fuel cell degradation resulting from shutdown and start-up of the fuel cell unit, an expected efficiency loss of the power assembly during the time period, and an expected fuel saving during the time period.
10. The method according to claim 1 , wherein the power assembly comprises two or more fuel cell units, and wherein identifying the time period comprises identifying a time period during which the power assembly is expected to be able to deliver power in accordance with the power demand with at least one of the at least two fuel cell units shut down, and wherein, in response to the identified time period being larger than the time threshold, said at least one fuel cell unit is scheduled to be shut down during at least a part of the identified time period.
11. The method according to claim 10 , wherein the time threshold is set to a value which is specific for each one of the two or more fuel cell units.
12. The method according to claim 1 , wherein the power assembly is adapted to deliver power contributing to the propulsion of a vehicle, and wherein predicting the power demand comprises:
receiving vehicle related information comprising at least one of traffic information for an expected travelling route of the vehicle during the prediction time horizon, terrain information for the expected travelling route, topographic information for the expected travelling route during the prediction time horizon, weather information for the expected travelling route during the prediction time horizon, and vehicle gross weight information, and
using said received vehicle related information for predicting the power demand over the prediction time horizon.
13. A control unit for controlling a power assembly, the control unit being configured to perform the method according to claim 1 .
14. A power assembly comprising one or more fuel cell units and an electric energy storage system for storing excess electric energy produced by the one or more fuel cell units, the power assembly further comprising the control unit according to claim 13 .
15. A vehicle comprising a power assembly according to claim 14 , wherein the power assembly is adapted to deliver power contributing to the propulsion of the vehicle.
16. A computer program comprising program code for performing the method of claim 1 when the program code is run on a computer.
17. A non-transitory computer readable medium carrying a computer program comprising program code for performing the method of claim 1 when the program code is run on a computer.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP22179034.8 | 2022-06-14 | ||
EP22179034.8A EP4292865A1 (en) | 2022-06-14 | 2022-06-14 | A method for controlling a power assembly |
Publications (1)
Publication Number | Publication Date |
---|---|
US20230398906A1 true US20230398906A1 (en) | 2023-12-14 |
Family
ID=82058501
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US18/334,798 Pending US20230398906A1 (en) | 2022-06-14 | 2023-06-14 | Method for controlling a power assembly |
Country Status (5)
Country | Link |
---|---|
US (1) | US20230398906A1 (en) |
EP (1) | EP4292865A1 (en) |
JP (1) | JP2023182545A (en) |
KR (1) | KR20230171896A (en) |
CN (1) | CN117227589A (en) |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP5910439B2 (en) * | 2012-09-28 | 2016-04-27 | 三菱自動車工業株式会社 | Power control device |
KR101852888B1 (en) | 2013-03-26 | 2018-06-04 | 한화지상방산 주식회사 | Method for operating hybrid power supply system |
EP3173284B1 (en) * | 2015-11-25 | 2019-12-11 | Magna Steyr Fahrzeugtechnik AG & Co KG | Method for operating a fuel cell |
JP7124678B2 (en) * | 2018-12-05 | 2022-08-24 | トヨタ自動車株式会社 | fuel cell system |
-
2022
- 2022-06-14 EP EP22179034.8A patent/EP4292865A1/en active Pending
-
2023
- 2023-06-09 JP JP2023095315A patent/JP2023182545A/en active Pending
- 2023-06-12 CN CN202310692599.9A patent/CN117227589A/en active Pending
- 2023-06-14 US US18/334,798 patent/US20230398906A1/en active Pending
- 2023-06-14 KR KR1020230075877A patent/KR20230171896A/en unknown
Also Published As
Publication number | Publication date |
---|---|
CN117227589A (en) | 2023-12-15 |
EP4292865A1 (en) | 2023-12-20 |
KR20230171896A (en) | 2023-12-21 |
JP2023182545A (en) | 2023-12-26 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US9496748B2 (en) | Integrated power system control method and related apparatus with energy storage element | |
US7078877B2 (en) | Vehicle energy storage system control methods and method for determining battery cycle life projection for heavy duty hybrid vehicle applications | |
JP4306746B2 (en) | Vehicle power supply | |
CN107490766B (en) | System and method for measuring insulation resistance of fuel cell vehicle | |
US20130175858A1 (en) | Electric vehicle | |
CN111216596A (en) | Fuel cell whole vehicle energy management method and device, vehicle and storage medium | |
KR20110054135A (en) | Soc band strategy for hev | |
KR101664077B1 (en) | Device for controlling mode change of hybrid electric vehicle and method for controlling mode change using the same | |
US9172247B2 (en) | Power supply system with controlled power storage | |
US10343552B2 (en) | Heterogeneous electrical energy storage system | |
US11345255B2 (en) | Emergency electric power supply system, emergency electric power supply method, and storage medium | |
CN114559822A (en) | Load reduction control method, device and equipment for fuel cell engine | |
KR20110024307A (en) | Soc band strategy for hev | |
CN111775758B (en) | Power supply control method and device for charging station, computer equipment and storage medium | |
KR101500121B1 (en) | Method for auxilary battery power charge control | |
US20230398906A1 (en) | Method for controlling a power assembly | |
CN112140888A (en) | Control device for vehicle-mounted power supply device | |
US20230271529A1 (en) | A method for controlling an energy storage system of a vehicle | |
KR20200126135A (en) | Mileage increase method by using load control of electric vehicle | |
US20230398907A1 (en) | Method for controlling a power assembly | |
WO2023110070A1 (en) | A method for controlling a fuel cell system | |
CN111817417B (en) | Charging method and device of lead-acid storage battery for 12V start and stop and vehicle | |
JP2021023015A (en) | Vehicle electrical power system | |
EP2587607B1 (en) | Integrated power system control method and related apparatus with energy storage element | |
CN113580939B (en) | Power conservation method for vehicle-mounted battery, vehicle and readable storage medium |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STPP | Information on status: patent application and granting procedure in general |
Free format text: DOCKETED NEW CASE - READY FOR EXAMINATION |